阿尔茨海默病患者大脑T_2*值测量的临床研究

The clinical study of regional T_2* value changes in Alzheimer’s disease brain

目的:探究阿尔茨海默病(Alzheimer’s disease,AD)患者MRT2*值和R2*值的异常变化及这种异常与临床心理量表评分的相关性。材料和方法:26例AD患者及20例年龄相匹配的健康对照者均在3.0TMR系统中进行头部检查。采用一个多回波快速场回波序列获得T2*图,测量双侧海马、颞叶皮层、枕叶皮层、丘脑、壳核及苍白球所画感兴趣区的T2*值,计算相应的R2*值,比较AD组和健康对照组间T2*值和R2*值的差异;并检验AD患者上述部位脑结构T2*值和R2*值与简短精神状态量表(MMSE)评分的相关性。结果:与健康对照组比较,AD组海马、颞叶皮层及苍白球的T2*值减低、R2*值升高,且差异具有统计学意义(P<0.05)。AD患者的海马、颞叶皮层及苍白球的T2*值与MMSE评分呈正相关(相关系数分别为0.48、0.56和0.44,P<0.05),其R2*值与MMSE评分呈负相关(相关系数分别为-0.49、-0.58和-0.43,P<0.05)。结论:AD患者脑内T2*值和R2*值明显异常,并与临床心理量表评分显著相关,提示脑T2*值和R2*值的测量可能为今后AD的临床诊断及病情监测提供客观依据。

Objective： To explore T2＊ values and R2＊ values in several cerebral regions in patients with Alzheimer＇s disease（AD）, and to evaluate the correlation between T2＊ and R2＊ values in AD patients and clinical mental scale scores. Methods： Twenty-six AD patients and 20 healthy control subjects were performed using a multi-echo fast field echo sequence at a 3.0T MRI scanner. The T2＊ values were read from region of interest （ROI） drawn at several cerebral regions on the T2＊ maps. And the R2＊ values were calculated. The difference of T2＊ and R2＊ values in cerebral structures between AD patients and control subjects was compared. And the correlation between T2＊ and R2＊ values in AD patients and mini-mental state examination （MMSE） score was tested. Results： Compared with control subjects, the T2＊ values of the hippocampus, globus pallidus and temporal cortex in patients with AD were lower, the R2＊ values in these regions in AD patients were significantly in- creased. The T2＊ values of the hippocampus, temporal cortex and globus pallidus in patients with AD correlated positively with the MMSE score （r=0.48, 0.56, 0.44 respectively, all P〈0.05）. The correlation coefficients between the R2＊ values of these structures in AD patients and MMSE score were negative （r=-0.49, -0.58, -0.43 respectively, all P〈0.05）. Conclusions： The T2＊ and R2＊ values of cerebral regions in AD were significantly abnormal and were correlated with clinical mental scale scores, which suggested the measurements of T2＊ and R2＊ might be helpful in the diagnosis and longitudinal monitoring for AD.